The Association of Smoking Status and Clustering of Obesity and Depression on the Risk of Early-Onset Cardiovascular Disease in Young Adults: A Nationwide Cohort Study

BACKGROUND AND OBJECTIVES

To evaluate the impact of smoking in young adults on the risk of cardiovascular disease (CVD) and the clustering effect of behavioral risk factors such as smoking, obesity, and depression.

METHODS

A Korean nationwide population-based cohort of a total of 3,280,826 participants aged 20-39 years old who underwent 2 consecutive health examinations were included. They were followed up until the date of CVD (myocardial infarction [MI] or stroke), or December 2018 (median, 6 years).

RESULTS

Current smoking, early age of smoking initiation, and smoking intensity were associated with an increased risk of CVD incidence. Even after quitting smoking, the risk of MI was still high in quitters compared with non-smokers. Cigarette smoking, obesity, and depression were independently associated with a 1.3-1.7 times increased risk of CVD, and clustering of 2 or more of these behavioral risk factors was associated with a 2-3 times increased risk of CVD in young adults.

CONCLUSIONS

In young adults, cigarette smoking was associated with the risk of CVD, and the clustering of 2 or more behavioral risk factors showed an additive risk of CVD.

The Association between Duration of Noise Exposure in the Workplace and Glucose Metabolism Status: Evidence from the Korea National Health and Nutrition Examination Survey

BACKGROUND

This study aimed to evaluate the association between the duration of workplace noise exposure and glucose metabolism status in a nationally representative Korean sample.

METHODS

This cross-sectional study included 3,534 participants aged ≥40 years without tinnitus or hearing loss from the Korea National Health and Nutrition Examination Survey (2018). The primary exposure was noise in the workplace and its duration. We divided the noise exposure group into four groups according to the duration of noise exposure (<3 years, 3-10 years, 10-20 years, and ≥20 years). The primary outcomes were fasting blood sugar (FBS), hemoglobin A1c (HbA1c), and pre-diabetes and diabetes diagnosed using FBS. Logistic and linear regression analyses were used to test the association between noise exposure and glycemic status.

RESULTS

After adjustment, HbA1c levels were significantly higher in the noise exposure than in the non-noise exposure group. HbA1c levels were significantly higher in those exposed to occupational noise for more than 20 years than in others. In the subgroup analysis among those who had been exposed to noise for >20 years, the non-aerobic physical activity group had significantly higher HbA1c levels than the physical activity group. Furthermore, among those who had been exposed to noise for >20 years, the without hearing protection group had significantly higher HbA1c levels than those using hearing protection.

CONCLUSION

The association between noise exposure and the prevalence of diabetes is unclear. However, our study clearly suggests that there is a relationship between elevated HbA1c levels and workplace noise exposure and that a long period of workplace noise exposure, no physical activity, and not wearing a hearing protection device could increase the risk of diabetes.

Tuberculosis and Risk of Ischemic Stroke: A Nationwide Cohort Study

BACKGROUND

Conflicting results exist regarding the risk of ischemic stroke in tuberculosis survivors. We aimed to estimate the risk of ischemic stroke using a nationwide population-based retrospective cohort.

METHODS

We gathered data from the Korean National Health Insurance Service on tuberculosis survivors and 1:1 age- and sex-matched non-tuberculosis cases. Eligible participants were followed up from 1 year after tuberculosis diagnosis to the date of ischemic stroke event, date of death, or until the end of the study period (December 31, 2018), whichever came first. Cox proportional hazard regression and stratified analyses were performed to identify any related factors.

RESULTS

During follow-up periods of 3.8 years for patients with tuberculosis and matched non-tuberculosis cases, 1.3% of patients with tuberculosis (941/72 863) and 1.0% of matched non-tuberculosis cases (707/72 863) developed ischemic stroke. The overall risk of ischemic stroke was higher in tuberculosis patients (adjusted hazard ratio: 1.22 [95% CI, 1.10-1.36]) compared with the matched non-tuberculosis cases. A stratified analysis showed that patients with tuberculosis had increased risk of ischemic stroke regardless of age, sex, smoking status, alcohol consumption, physical activity, body mass index, and Charlson Comorbidity Index score.

CONCLUSIONS

Tuberculosis survivors had a higher risk of ischemic stroke than their matched non-tuberculosis cases. The results of this study suggest that tuberculosis is a crucial infectious factor associated with increased incidence of ischemic stroke.

Association Between Changes in Alcohol Consumption and Cancer Risk

IMPORTANCE

Although numerous studies have shown an association between alcohol consumption and cancer, how changes in drinking behavior increase or decrease the incidence of cancer is not well understood.

OBJECTIVE

To investigate the association between the reduction, cessation, or increase of alcohol consumption and the development of alcohol-related cancers and all cancers.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study analyzed adult beneficiaries in the Korean National Health Insurance Service. Participants (aged ≥40 years) included those who underwent a national health screening in both 2009 and 2011 and had available data on their drinking status. Data were analyzed from April 16 to July 6, 2020.

EXPOSURES

Alcohol consumption level, which was self-reported by participants in health screening questionnaires, was categorized into none (0 g/d), mild (<15 g/d), moderate (15-29.9 g/d), and heavy (≥30 g/d) drinking. Based on changes in alcohol consumption level from 2009 to 2011, participants were categorized into the following groups: nondrinker, sustainer, increaser, quitter, and reducer.

MAIN OUTCOMES AND MEASURES

The primary outcome was newly diagnosed alcohol-related cancers (including cancers of the head and neck, esophagus, colorectum, liver, larynx, and female breast), and the secondary outcome was all newly diagnosed cancers (except for thyroid cancer).

RESULTS

Among the 4 513 746 participants (mean [SD] age, 53.6 [9.6] years; 2 324 172 [51.5%] men), the incidence rate of cancer was 7.7 per 1000 person-years during a median (IQR) follow-up of 6.4 (6.1-6.6) years. Compared with the sustainer groups at each drinking level, the increaser groups had a higher risk of alcohol-related cancers and all cancers. The increased alcohol-related cancer incidence was associated with dose; those who changed from nondrinking to mild (adjusted hazard ratio [aHR], 1.03; 95% CI, 1.00-1.06), moderate (aHR, 1.10; 95% CI, 1.02-1.18), or heavy (aHR, 1.34; 95% CI, 1.23-1.45) drinking levels had an associated higher risk than those who did not drink. Those with mild drinking levels who quit drinking had a lower risk of alcohol-related cancer (aHR, 0.96; 95% CI, 0.92-0.99) than those who sustained their drinking levels. Those with moderate (aHR, 1.07; 95% CI, 1.03-1.12) or heavy (aHR, 1.07; 95% CI, 1.02-1.12) drinking levels who quit drinking had a higher all cancer incidence than those who sustained their levels, but when quitting was sustained, this increase in risk disappeared. Compared with sustained heavy drinking, reduced heavy drinking levels to moderate levels (alcohol-related cancer: aHR, 0.91 [95% CI, 0.86-0.97]; all cancers: aHR, 0.96 [95% CI, 0.92-0.99]) or mild levels (alcohol-related cancer: aHR, 0.92 [95% CI, 0.86-0.98]; all cancers: aHR, 0.92 [95% CI, 0.89-0.96]) were associated with decreased cancer risk.

CONCLUSIONS AND RELEVANCE

Results of this study showed that increased alcohol consumption was associated with higher risks for alcohol-related and all cancers, whereas sustained quitting and reduced drinking were associated with lower risks of alcohol-related and all cancers. Alcohol cessation and reduction should be reinforced for the prevention of cancer.

Changes in Physical Activity and the Risk of Dementia in Patients With New-Onset Type 2 Diabetes: A Nationwide Cohort Study

OBJECTIVE

We investigated the association between interval changes in physical activity (PA) and dementia risk among patients with new-onset type 2 diabetes.

RESEARCH DESIGN AND METHODS

We identified 133,751 participants newly diagnosed with type 2 diabetes in a health screening (2009-2012), with a follow-up health screening within 2 years (2010-2015). PA level changes were categorized into continuous lack of PA, decreaser, increaser, and continuous PA groups. Dementia was determined using dementia diagnosis codes and antidementia drug prescriptions.

RESULTS

During the median follow-up of 4.8 years, 3,240 new cases of all-cause dementia developed. Regular PA was associated with lower risks of all-cause dementia (adjusted hazard ratio [aHR] 0.82; 95% CI 0.75-0.90), Alzheimer disease (AD) (aHR 0.85; 95% CI 0.77-0.95), and vascular dementia (VaD) (aHR 0.78; 95% CI 0.61-0.99). Increasers who started to engage in regular PA had a lower risk of all-cause dementia (aHR 0.86; 95% CI 0.77-0.96). Moreover, the risk was further reduced among those with continuous regular PA: all-cause dementia (aHR 0.73; 95% CI 0.62-0.85), AD (aHR 0.74; 95% CI 0.62-0.88), and VaD (aHR 0.62; 95% CI 0.40-0.94). Consistent results were noted in various subgroup analyses.

CONCLUSIONS

Regular PA was independently associated with lower risks of all-cause dementia, AD, and VaD among individuals with new-onset type 2 diabetes. Those with continuous regular PA and, to a lesser extent, those who started to engage in regular PA had a lower risk of dementia. Regular PA should be encouraged to prevent dementia in high-risk populations and those with new-onset type 2 diabetes.

Association of Change in Alcohol Consumption With Risk of Ischemic Stroke

BACKGROUND

The effect of serial change in alcohol consumption on stroke risk has been limitedly evaluated. We investigated the association of change in alcohol consumption with risk of stroke.

METHODS

This study is a population-based retrospective cohort study from National Health Insurance Service database of all Koreans. Four lakh five hundred thirteen thousand seven hundred forty-six participants aged ≥40 years who underwent 2 subsequent national health examinations in both 2009 and 2011. Alcohol consumption was assessed by average alcohol intake (g/day) based on self-questionnaires and categorized into non-, mild, moderate, and heavy drinking. Change in alcohol consumption was defined by shift of category from baseline. Cox proportional hazards model was used with adjustment for age, sex, smoking status, regular exercise, socioeconomic information, and comorbidities, Charlson Comorbidity Index, systolic blood pressure, and laboratory results. Subgroup analysis among those with the third examination was conducted to reflect further change in alcohol consumption.

RESULTS

During 28 424 497 person-years of follow-up, 74 923 ischemic stroke events were identified. Sustained mild drinking was associated with a decreased risk of ischemic stroke (adjusted hazard ratio, 0.88 [95% CI, 0.86-0.90]) compared with sustained nondrinking, whereas sustained heavy drinking was associated with an increased risk of ischemic stroke (adjusted hazard ratio, 1.06 [95% CI, 1.02-1.10]). Increasing alcohol consumption was associated with an increased risk of ischemic stroke (adjusted hazard ratio, 1.11 [95% CI, 1.06-1.17] from mild to moderate; adjusted hazard ratio, 1.28 [95% CI, 1.19-1.38] from mild to heavy) compared with sustained mild drinkers. Reduction of alcohol consumption from heavy to mild level was associated with 17% decreased risk of ischemic stroke through 3× of examinations.

CONCLUSIONS

Light-to-moderate alcohol consumption is associated with a decreased risk of ischemic stroke, although it might be not causal and could be impacted by sick people abstaining from drinking. Reduction of alcohol consumption from heavy drinking is associated with a decreased risk of ischemic stroke.

Blood Pressure Variability and the Risk of Fracture: A Nationwide Cohort Study

CONTEXT

Although blood pressure variability (BPV) is associated with various health outcomes, only 1 study suggested that BPV is correlated with hip fractures. As cardiovascular disease and fractures share similar pathophysiology, there might be a link between BPV and fractures.

OBJECTIVE

To investigate the association between BPV and the incident fractures.

DESIGN

Retrospective cohort study.

SETTING

Population-based, using the Korean National Health Insurance System database.

PATIENTS OR OTHER PARTICIPANTS

A total of 3 256 070 participants aged ≥50 who participated in ≥3 health examinations within the previous 5 years, including the index year (2009-2010), were included. Outcome data were obtained through the end of 2016.

EXPOSURE

BPV was calculated using variability independent of the mean. High variability was defined as the highest quartile of variability.

MAIN OUTCOME MEASURES

Newly diagnosed fractures.

RESULTS

During the median follow-up of 7.0 years, there were 337 045 cases of any fracture (10.4%). After adjusting for age, sex, income, lifestyle factors, and comorbidities, a higher risk of fracture was observed with higher quartiles of BPV than the lowest quartile group: the adjusted hazard ratios (95% CIs) for incident any fracture were 1.07 (1.06-1.08) in the higher quartile of systolic BPV, 1.06 (1.05-1.07) in that of diastolic BPV, and 1.07 (1.06-1.08) in that of both systolic and diastolic BPV. Consistent results were noted for vertebral fractures and hip fractures, as well as in various subgroup analyses.

CONCLUSIONS

A positive association was noted between higher BPV and fracture incidence. BPV is an independent predictor for developing fracture.

Effect of smoking reduction, cessation, and resumption on cancer risk: A nationwide cohort study

BACKGROUND

The objective of this study was to investigate the effects of reduction, cessation, and resumption of smoking on cancer development.

METHODS

The authors identified 893,582 participants who currently smoked, had undergone a health screening in 2009, and had a follow-up screening in 2011. Among them, 682,996 participated in a third screening in 2013. Participants were categorized as quitters, reducers I (≥50% reduction), reducers II (<50% reduction), sustainers (referent), or increasers (≥20% increase). Outcome data were obtained through December 31, 2018.

RESULTS

Reducers I exhibited a decreased risk of all cancers (adjusted hazard ratio [aHR], 0.96; 95% confidence interval [CI], 0.93-0.99), smoking-related cancers (aHR, 0.95; 95% CI, 0.92-0.99), and lung cancer (aHR, 0.83; 95% CI, 0.77-0.88). Quitters had the lowest risk of all cancers (aHR, 0.94; 95% CI, 0.92-0.96), smoking-related cancers (aHR, 0.91; 95% CI, 0.89-0.93), and lung cancer (aHR, 0.79; 95% CI, 0.76-0.83). In further analysis with 3 consecutive screenings, additional smoking reduction (from reducers II to reducers I) lowered the risk of lung cancer (aHR, 0.74; 95% CI, 0.58-0.94) in comparison with sustainers. Quitting among reducers I further decreased the risk of all cancers (aHR, 0.90; 95% CI, 0.80-1.00), smoking-related cancers (aHR, 0.81; 95% CI, 0.81-0.92), and lung cancer (aHR, 0.66; 95% CI, 0.52-0.84) in comparison with sustainers. Smoking resumption after quitting, even at a lower level, increased the risk of smoking-related cancers (aHR, 1.19; 95% CI, 1.06-1.33) and lung cancer (aHR, 1.48; 95% CI, 1.21-1.80) in comparison with sustained quitting.

CONCLUSIONS

Smoking cessation and, to a lesser extent, smoking reduction decreased the risks of cancer. Smoking resumption increased cancer risks in comparison with sustained quitting.

LAY SUMMARY

Worldwide, tobacco use is the single leading preventable risk factor for cancer and cancer death. This study examined the effects of reduction, cessation, and resumption of smoking on cancer development by measuring smoking behavior repetitively. Although smoking reduction has a substantial cancer prevention benefit for those who cannot quit, cessation should be encouraged whenever possible. Quitters should be monitored to ensure that they do not resume smoking.

Female reproductive factors and risk of joint replacement arthroplasty of the knee and hip due to osteoarthritis in postmenopausal women: a nationwide cohort study of 1.13 million women

OBJECTIVES

Previous studies of the relationships between female reproductive factors and osteoarthritis (OA) have shown conflicting results. In this study, we aimed to explore the relationships between reproductive factors and joint replacement arthroplasty of the knee (TKRA) and hip (THRA) in a large nationwide population-based cohort of postmenopausal Korean women.

METHODS

We included 1,134,680 subjects who participated in national health examinations in 2009 in the study. The study outcomes were incident THRA or TKRA due to severe hip or knee OA. The relationships between reproductive factors and THRA or TKRA were evaluated using a multivariable-adjusted proportional hazards model.

RESULTS

During a mean follow-up duration of 8.2 years, 1,610 incident THRA cases and 60,670 incident TKRA cases were observed. Later age at menarche, longer breastfeeding, HRT and OC use were associated with increased risk of TKRA for severe knee OA, while later age at menopause and longer reproductive span were associated with decreased risk. With regard to THRA for severe hip OA, later menarche, longer breastfeeding, HRT more than 5 years, and OC use more than 1 year were associated with higher risk. The associations between reproductive factors and severe OA were more pronounced in underweight and younger subjects.

CONCLUSION

We found that shorter estrogen exposure was associated with higher risk of TKRA due to severe knee OA, and such associations were more pronounced in underweight and younger subjects. The association between shorter estrogen exposure and THRA was not robust.

Associations between alcohol consumption patterns and risk of multiple myeloma: A nationwide cohort study in South Korea

BACKGROUND

Among the potential modifiable risk factors, the association between alcohol consumption and the risk of multiple myeloma (MM) remains controversial. We investigated the effects of weekly average alcohol consumption and drinking pattern on the risk of MM using a nationwide representative database.

METHODS

We identified 11,737,467 subjects who participated in the Korean national health screening program in 2009-2010. Cox regression analyses were performed to calculate the risk of MM according to weekly alcohol consumption, drinking frequency, and amount per session.

RESULTS

During a mean follow-up period of 6.8 years after a one-year time lag, 6,981 subjects (3,921 men and 3,060 women) were diagnosed with MM. Compared with non-drinkers, all drinkers were at a significantly lower risk for MM. The risk of MM was reduced in a dose-dependent manner: mild drinkers, adjusted hazard ratio (aHR) 0.89, 95% confidence interval (CI) 0.84-0.95; moderate drinkers, aHR 0.83, 95% CI 0.76-0.91; and heavy drinkers, aHR 0.76, 95% CI 0.69-0.85. Furthermore, both drinking frequency and amount per drinking session showed inverse association with the risk of MM.

CONCLUSIONS

Our large population-based study suggested an inverse dose-dependent association between total average alcohol consumption and the risk of MM, and drinking frequency and amount per drinking session seemed to not differ in their relative contribution to the risk of MM.

IMPACT

Based on the unprecedently large number of study population analyzed in this study, our study provides solid epidemiologic evidence of alcohol consumption on MM risk.

Body Mass Index, Diabetes, and Risk of Tuberculosis: A Retrospective Cohort Study

Although both diabetes mellitus (DM) and underweight are associated with increased risk of tuberculosis (TB), there are limited data evaluating TB risk while considering two factors simultaneously—body mass index (BMI) and DM. A retrospective cohort study was performed with 10,087,903 participants of the Korean National Health Screening Program in 2009. The cohort was followed up to the date of TB incidence, death, or until December 31, 2018. We compared the incidence and risk of TB according to BMI category and DM. During the 7.3-year follow-up duration, the incidence of TB was 0.92 per 1,000 person-years in the normal weight without DM, 2.26 in the normal weight with DM, 1.80 in the underweight without DM, and 5.35 in the underweight with DM. Compared to the normal weight without DM, the normal weight with DM, the underweight without DM, and the underweight with DM showed a 1.51-fold (95% CI, 1.46–1.57), a 2.21-fold (95% CI, 2.14–2.28), and a 3.24-fold (95% CI, 2.95–3.56) increased risk of TB, respectively. However, compared to the normal weight without DM, the severely obese without DM and those with DM showed a 0.37 (95% CI, 0.36–0.38) and a 0.42 (95% CI, 0.36–0.48)-fold decreased risk of TB, respectively. There was no significant joint effect of BMI and DM on the risk of incident TB in the overall population; a synergistic effect of underweight and DM was evident in participants <65 years of age, current smokers, and heavy drinkers. In conclusion, being underweight or DM individually increases the risk of incident TB. Based on our study results, a focused screening of incident TB in patients with DM may be beneficial.

Association between obesity and the risk of gastric cancer in premenopausal and postmenopausal women: A nationwide cohort study

BACKGROUND AND AIM

Obesity was suggested to increase the incidence of gastric cancer (GC) in women, but results from previous studies were inconsistent. We investigated the relationship between obesity and the risk of GC according to menopausal status.

METHODS

We enrolled 1 418 180 premenopausal and 4 854 187 postmenopausal women aged ≥ 40 years using the Korean National Health Insurance System Cohort (2009-2014). We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) for GC incidence according to body mass index (BMI) and waist circumference (WC) using the Cox proportional hazards models.

RESULTS

During the mean follow-up period of 7.2 years, 42 441 women were newly diagnosed with GC. Compared with the group with BMI 18.5-22.9 kg/m² , the adjusted HRs (95% CIs) for GC in the groups with BMI < 18.5, 23-24.9, 25-29.9, and ≥ 30 kg/m² were 1.12 (0.95-1.33), 0.96 (0.89-1.04), 1.02 (0.94-1.11), and 0.99 (0.83-1.18), respectively, for premenopausal women and 1.07 (1.00-1.14), 1.01 (0.99-1.04), 1.03 (1.00-1.05), and 1.11 (1.10-1.16), respectively, for postmenopausal women. Compared with the group with WC 65-74.9 cm, the adjusted HRs (95% CIs) for GC for the groups with WC < 65, 75-84.9, 85-94.9, and ≥ 90 cm were 1.00 (0.88-1.15), 1.03 (0.96-1.11), 1.10 (0.99-1.22), and 1.02 (0.81-1.27), respectively, for premenopausal women and 1.01 (0.94-1.09), 1.01 (0.99-1.04), 1.09 (1.06-1.13), and 1.14 (1.09-1.19), respectively, for postmenopausal women.

CONCLUSIONS

We found a positive association between the highest BMI and WC category and risk of GC in postmenopausal women; however, such an association was not evident in premenopausal women.

Being Underweight Increases the Risk of Non-Cystic Fibrosis Bronchiectasis in the Young Population: A Nationwide Population-Based Study

Although body mass index (BMI) is a potential risk factor for bronchiectasis in young adults, the association between BMI and incident bronchiectasis has not been well elucidated. This study included 6,329,838 individuals aged 20-40 years from the Korean National Health Insurance Service database 2009-2012 who were followed up until the date of the diagnosis of bronchiectasis, death, or 31 December 2018. We evaluated the incidence and risk of bronchiectasis according to the BMI category. The incidence rate of bronchiectasis increased as BMI decreased in a dose-dependent manner (p for trend <0.01). In multivariable Cox regression analysis, being underweight was an independent risk factor for the development of bronchiectasis, with a hazard ratio of 1.24 (95% confidence interval, 1.19-1.30) compared to being normal weight. In subgroup analysis, the effect of being underweight on the development of bronchiectasis was more evident in males and older individuals (30-40 years) than females and younger individuals (20-29 years), respectively (p for interaction <0.01 for both). These results remained significant in subgroup analysis in which subjects with comorbidities related to being underweight were excluded. Being underweight may be a novel risk factor for the development of bronchiectasis in young adults.

Diabetes Status and Association With Risk of Tuberculosis Among Korean Adults

IMPORTANCE

The risk of tuberculosis (TB) associated with diabetes status, considering impaired fasting glucose or duration of diabetes, has not been well established.

OBJECTIVE

To evaluate the association of diabetes status with the development of TB in the general population.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study used data from the Korean National Health Insurance System database. Adult participants without a history of TB who underwent a health screening in 2009 were included. Eligible participants were followed up for incident TB cases from 1 year after the day of health screening until December 31, 2018. Data analysis was performed from September 2019 to September 2020.

EXPOSURES

Five levels of diabetes status were evaluated: normal glucose, impaired fasting glucose (considered as without diabetes), new-onset diabetes, diabetes duration less than 5 years, and diabetes duration 5 years or longer (considered as having diabetes).

MAIN OUTCOMES AND MEASURES

Newly diagnosed TB.

RESULTS

Among 4 423 177 participants, the mean (SD) age was 46.5 (13.9) years, and there were 2 597 142 men (58.7%). A total of 26 458 participants (0.6%) received a diagnosis of TB within a median (interquartile range) of 8.3 (8.1-8.6) years of follow-up. An increased risk of TB was observed in participants with diabetes compared with those without diabetes (adjusted hazard ratio [aHR], 1.48; 95% CI, 1.42-1.53). Although participants with impaired fasting glucose did not show an increased risk of TB incidence (aHR, 0.97; 95% CI, 0.93-1.01), the risk of TB incidence increased with diabetes duration (new-onset diabetes, aHR, 1.32; 95% CI, 1.23-1.42; diabetes duration <5 years, aHR, 1.45; 95% CI, 1.36-1.54; diabetes duration ≥5 years, aHR, 1.57; 95% CI, 1.48-1.66). Among participants with new-onset diabetes, compared with those in the lowest decile (fasting plasma glucose [FPG] level ≥126 but <128 mg/dL), the risk of TB was significantly increased for those in the highest decile (FPG level ≥202 mg/dL, aHR, 1.79; 95% CI, 1.42-2.26).

CONCLUSIONS AND RELEVANCE

These findings suggest that longer diabetes duration is associated with development of TB, showing a dose-response association. Among participants with new-onset diabetes, incident TB was more common among those with FPG levels greater than or equal to 202 mg/dL.

Association of the Frequency and Quantity of Alcohol Consumption With Gastrointestinal Cancer

IMPORTANCE

Although total alcohol consumption is a known risk factor for gastrointestinal (GI) cancers, few studies have attempted to assess the pattern of alcohol drinking in association with GI cancers.

OBJECTIVE

To evaluate the relative association of the frequency of drinking vs the amount of alcohol consumed per occasion with the development of GI cancers.

DESIGN, SETTING, AND PARTICIPANTS

A population-based retrospective cohort study used data from the Korean National Health Insurance System database on 11 737 467 participants without cancer who underwent a national health screening program from January 1, 2009, to December 31, 2010. Participants were followed up from the year after their health screening date until they received a diagnosis of GI cancer, death, or December 31, 2017. The median follow-up duration was 6.4 years (interquartile range, 6.4-7.4 years). Statistical analysis was performed from January 1, 2019, to March 31, 2020.

EXPOSURES

Weekly alcohol consumption (nondrinker [0 g/week], mild drinker [0-104 g/week], moderate drinker [105-209 g/week], and heavy drinker [≥210 g/week]), drinking frequency, and amount per occasion.

MAIN OUTCOMES AND MEASURES

Incident GI cancers at 6 specific sites (esophagus, stomach, colorectal, liver, biliary, and pancreas).

RESULTS

Among 11 737 467 participants (6 124 776 women [52.2%]; mean [SD] age, 54.6 [10.4] years), 319 202 (2.7%) developed GI cancer. Compared with nondrinkers, the risk of GI cancer was higher for mild drinkers (adjusted hazard ratio [aHR], 1.04; 95% CI, 1.03-1.05), moderate drinkers (aHR, 1.14; 95% CI, 1.12-1.15), and heavy drinkers (aHR, 1.28; 95% CI, 1.26-1.29). The risk of GI cancer increased linearly with the frequency of drinking in a dose-dependent manner (aHR, 1.39; 95% CI, 1.36-1.41 for individuals who drink every day). In contrast, the risk of GI cancer appeared to increase with consumption up to 5 to 7 units per occasion (aHR, 1.15; 95% CI, 1.14-1.16), and then the HRs were no higher for those with a higher intake per session than 5 to 7 units (8-14 units per occasion: aHR, 1.11; 95% CI, 1.09-1.12; >14 units per occasion: aHR, 1.11; 95% CI, 1.08-1.14). Given similar weekly alcohol consumption levels, the risk of GI cancer increased with a higher frequency of drinking and decreased with a higher amount per occasion. Risk patterns for 6 specific cancers were generally similar to that of all GI cancers.

CONCLUSIONS AND RELEVANCE

In this cohort study, frequent drinking was a more important risk factor for incident GI cancers than the amount of alcohol consumed per occasion. Individuals should be cautioned about regular consumption of small amounts of alcohol in addition to the total amount of alcohol consumption or amount per occasion.

Anemia, sarcopenia, physical activity, and the risk of tuberculosis in the older population: a nationwide cohort study

Background:

The aim of this study was to investigate whether physical activity, sarcopenia, and anemia are associated an with increased risk of tuberculosis (TB) among the older population.

Methods:

We included 1,245,640 66-year-old subjects who participated in the National Screening Program for Transitional Ages for Koreans from 2009 to 2014. At baseline, we assessed common health problems in the older population, including anemia and sarcopenia. The subjects’ performance in the timed up-and-go (TUG) test was used to predict sarcopenia. The incidence of TB was determined using claims data from the National Health Insurance Service database.

Results:

The median follow-up duration was 6.4 years. There was a significant association between the severity of anemia and TB incidence, with an adjusted hazard ratio (aHR) of 1.28 [95% confidence interval (CI), 1.20–1.36] for mild anemia and 1.69 (95% CI, 1.51–1.88) for moderate to severe anemia. Compared with those who had normal TUG times, participants with slow TUG times (⩾15 s) had a significantly increased risk of TB (aHR 1.19, 95% CI, 1.07–1.33). On the other hand, both irregular (aHR 0.88, 95% CI 0.83–0.93) and regular (aHR 0.84, 95% CI, 0.78–0.92) physical activity reduced the risk of TB. Male sex, lower income, alcohol consumption, smoking, diabetes, and asthma/chronic obstructive pulmonary disease increased the risk of TB.

Conclusion:

The risk of TB among older adults increased with worsening anemia, sarcopenia, and physical inactivity. Physicians should be aware of those modifiable predictors for TB among the older population.

Association between physical performance and incidence of end-stage renal disease in older adults: a national wide cohort study

Background

Physical frailty has previously been associated with adverse clinical outcomes in patients with end-stage renal disease (ESRD). This study aimed to determine whether impaired physical performance at baseline is associated with the incidence of ESRD, using a nationwide database.

Methods

The timed up-and-go (TUG) test was used to assess physical frailty in 1,552,781 66-year-old individuals, using health examination database records from the Korean National Health Insurance Service. As a primary endpoint, incident ESRD was defined operationally using healthcare claims data from the Korean Health Insurance Review and Assessment Service.

Results

Our results showed that baseline kidney function was significantly worse in individuals with TUG results of > 10 s compared to individuals with an intact TUG performance (≤10 s). Kaplan-Meier analysis showed a stepwise dose-response relationship between baseline physical performance and the incidence rate of ESRD (log-rank test P-value of < 0.001). An increasing ESRD incidence rate trend with poor physical performance remained significant after adjusting for characteristics such as baseline glomerular filtration rate and proteinuria.

Conclusion

Poor baseline physical performance was associated with an increased risk of ESRD, suggesting possible interactions between systemic frailty and vascular aging processes.

Conditional Survival of Surgically Treated Patients with Lung Cancer: A Comprehensive Analyses of Overall, Recurrence-free, and Relative Survival

Purpose

Survival probability changes over time in cancer survivors. This study examined conditional survival in patients undergoing curative resection for non-small cell lung cancer (NSCLC).

Materials and Methods

Five-year conditional recurrence-free survival (CRFS), conditional overall survival (COS), and conditional relative survival (CRS) up to 10 years after surgery were calculated in patients who underwent NSCLC resection from 1994 to 2016. These rates were stratified according to age, sex, year of diagnosis, pathological stage, tumor histology, smoking status, comorbidity, and lung function.

Results

Five-year CRFS increased from 65.6% at baseline to 90.9% at 10 years after surgery. Early differences in 5-year CRFS according to stratified patient characteristics disappeared, except for age: older patients exhibited persistently lower 5-year CRFS. Five-year COS increased from 72.7% to 78.3% at 8 years and then decreased to 75.4% at 10 years. Five-year CRS increased from 79.0% at baseline to 86.8% at 10 years. Older age and higher pathologic stage were associated with lower 5-year COS and CRS up to 10 years after surgery. Female patients, those with adenocarcinoma histology, non-smokers, patient without comorbidities and had good lung function showed higher COS and CRS.

Conclusion

CRFS improved over time, but significant risk remained after 5 years. CRS slightly improved over time but did not reach 90%, suggesting significant excess mortality compared to the general population. Age and stage remained significant predictors of conditional survival several years after surgery. Our conditional survival estimates should help clinicians and patients make informed treatment and personal life decisions based on survivorship status.

Association of Female Reproductive Factors With Incidence of Fracture Among Postmenopausal Women in Korea

IMPORTANCE

Although estrogen level is positively associated with bone mineral density, there are limited data on the risk of fractures after menopause.

OBJECTIVE

To investigate whether female reproductive factors are associated with fractures among postmenopausal women.

DESIGN, SETTING, AND PARTICIPANTS

This population-based retrospective cohort study used data from the Korean National Health Insurance Service database on 1 272 115 postmenopausal women without previous fracture who underwent both cardiovascular and breast and/or cervical cancer screening from January 1 to December 31, 2009. Outcome data were obtained through December 31, 2018.

EXPOSURES

Information was obtained about reproductive factors (age at menarche, age at menopause, parity, breastfeeding, and exogenous hormone use) by self-administered questionnaire.

MAIN OUTCOMES AND MEASURES

Incidence of any fractures and site-specific fractures (vertebral, hip, and others).

RESULTS

Among the 1 272 115 participants, mean (SD) age was 61.0 (8.1) years. Compared with earlier age at menarche (≤12 years), later age at menarche (≥17 years) was associated with a higher risk of any fracture (adjusted hazard ratio [aHR], 1.24; 95% CI, 1.17-1.31) and vertebral fracture (aHR, 1.42; 95% CI, 1.28-1.58). Compared with earlier age at menopause (<40 years), later age at menopause (≥55 years) was associated with a lower risk of any fracture (aHR, 0.89; 95% CI, 0.86-0.93), vertebral fracture (aHR, 0.77; 95% CI, 0.73-0.81), and hip fracture (aHR, 0.88; 95% CI, 0.78-1.00). Longer reproductive span (≥40 years) was associated with lower risk of fractures compared with shorter reproductive span (<30 years) (any fracture: aHR, 0.86; 95% CI, 0.84-0.88; vertebral fracture: aHR, 0.73; 95% CI, 0.71-0.76; and hip fracture: aHR, 0.87; 95% CI, 0.80-0.95). Parous women had a lower risk of any fracture than nulliparous women (aHR, 0.96; 95% CI, 0.92-0.99). Although breastfeeding for 12 months or longer was associated with a higher risk of any fractures (aHR, 1.05; 95% CI, 1.03-1.08) and vertebral fractures (aHR, 1.22; 95% CI, 1.17-1.27), it was associated with a lower risk of hip fracture (aHR, 0.84; 95% CI, 0.76-0.93). Hormone therapy for 5 years or longer was associated with lower risk of any factures (aHR, 0.85; 95% CI, 0.83-0.88), while use of oral contraceptives for 1 year or longer was associated with a higher risk of any fractures (aHR, 1.03; 95% CI, 1.01-1.05).

CONCLUSIONS AND RELEVANCE

The findings of this cohort study suggest that female reproductive factors are independent risk factors for fracture, with a higher risk associated with shorter lifetime endogenous estrogen exposure. Interventions to reduce fracture risk may be needed for women at high risk, including those without osteoporosis.

Conditional relative survival and competing mortality in patients who underwent surgery for lung cancer: A nationwide cohort study

We aimed to investigate the conditional relative survival (CRS) and competing mortality in patients who underwent surgery for newly diagnosed lung cancer. Using a nationwide population-based database, we calculated 5-year CRS on 1 to 5 years survival after surgery. These rates were reported according to age, sex, socioeconomic status, comorbidities and treatment received. We also estimated cause-specific mortality with the consideration of competing risk. We identified 34 349 patients newly diagnosed with primary lung cancer from 2007 to 2013. The 5-year CRS after surgery was 71.7% at baseline improving steadily to 85.4% by 5 years, suggesting evidence of persistent excess mortality risk. Throughout the period, lung cancer was the most common cause of death, contributing to 83.6% mortality 1 year after surgery and 66.3% 5 years after surgery. Other causes of death included cardiovascular disease and respiratory disease, which increased continuously with time after surgery. CRS rates for patients with lung cancer improved over time but did not reach the level of the general population even 5 years after surgery. Although the main cause of death continues to be lung cancer, death from noncancer causes increased with time after surgery. Evidence-based decisions could be made on the dynamic risk profiles of the patients.

Obesity Has a Stronger Relationship with Colorectal Cancer in Postmenopausal Women than Premenopausal Women

BACKGROUND

To examine the relationship between obesity measured by waist circumference (WC) and body mass index (BMI) and the incidence of colorectal cancer in premenopausal and postmenopausal women.

METHODS

A total of 1,418,180 premenopausal and 4,854,187 postmenopausal women without cancer at baseline and ages over 40 were identified using the Korean National Health Insurance System Cohort during 2009 to 2014. The hazard ratio (HR) for colorectal cancer incidence was assessed according to menopausal state using Cox proportional hazards models.

RESULTS

During a mean follow-up period of 7.2 years, 7,094 and 57,449 colorectal cancer cases occurred in premenopausal and postmenopausal women, respectively. Compared with the reference group (WC 65-75), the HRs [95% confidence interval (CI)] of colorectal cancer in WC <65, 75-85, 85-95, and >95 groups were 1.01 (0.91-1.11), 1.02 (0.97-1.07), 1.09 (1.00-1.18), and 1.31 (1.12-1.52), respectively, in premenopausal women and 1.01 (0.95-1.17), 1.09 (1.07-1.12), 1.19 (1.00-1.18), and 1.30 (1.25-1.35), respectively, in postmenopausal women. Compared with the reference group (BMI 18.5-22.9), HRs (95% CI) for colorectal cancer in BMI <18.5, 23-25, 25-30, and >30 groups were 0.99 (0.87-1.14), 0.99 (0.94-1.06), 0.98 (0.92-1.04), and 1.06 (0.92-1.20), respectively, in premenopausal women. In postmenopausal women, those values were 0.99 (0.93-1.05), 1.05 (1.03-1.08), 1.11 (1.09-1.13), and 1.20 (1.16-1.25), respectively.

CONCLUSIONS

WC is associated with the risk of colorectal cancer in both groups of women, but this association was stronger in postmenopausal women than in premenopausal women. BMI increased the incidence of colorectal cancer only in postmenopausal women IMPACT: Obesity has a stronger relationship with colorectal cancer in postmenopausal women than in premenopausal women.